Commercial and industrial electronic meters are now including communication devices to allow for remote interrogation and remote meter reading. These communication products place increased pressure on the internal power supply to deliver large currents under a variety of different operating conditions. Wide range power supplies designed for commercial and industrial meters may have to operate as low as 46 VAC and as high as 530 VAC while delivering hundred of milliamperes of current.
As a result, many of the new power supply switching controller chips are designed for a variety of different applications and are not necessarily compatible with every aspect of an electronic meter's requirements. Such an area of concern is the auto-restart for controllers, such as the Power Integrations Topswitch® product. The controller chip is designed to be able to handle short circuit fault conditions that could result from battery charger applications and other special cases. The net result is that the controller chip can offer undesirable performance under certain operating conditions within the meter.
What is needed are circuits and methods that eliminate the auto-restart function in controller chips, such as the Power Integrations Topswitch® product.